episcopal vs pontifical

episcopal is not a noun while pontifical is a noun.

Word	Noun	Adjective	Verb	Adverb
episcopal	No	Yes	No	No
pontifical	Yes	Yes	No	No

As adjectives, episcopal and pontifical are synonyms defined as:

episcopal and pontifical: denoting or governed by or relating to a bishop or bishops

episcopal (noun)	pontifical (noun)
	the vestments and other insignia of a pontiff (especially a bishop)

episcopal (adjective)	pontifical (adjective)
denoting or governed by or relating to a bishop or bishops	denoting or governed by or relating to a bishop or bishops
	proceeding from or ordered by or subject to a pope or the papacy regarded as the successor of the Apostles
	puffed up with vanity